METHOD FOR PRODUCING POLYAMIDE-6 Russian patent published in 2024 - IPC C08G69/16 C08G69/46 B29B9/16 

FIELD: polyamide-6 production.

SUBSTANCE: method for production of polyamide-6 by obtaining a prepolymer during two-stage hydrolytic polymerization of caprolactam in the presence of an initiator, water in an amount of 1.0-1.3 wt.%, followed by the production of polyamide-6 granulate from the prepolymer melt, solid-phase additional polyamidation of the polyamide-6 granulate in flow of inert gas, nitrogen at a temperature of 175-180°C, and continuous combined drying-demonomerization in the solid phase of the resulting equilibrium granulate of polyamide-6 in a flow of inert gas, nitrogen at a temperature of 150-160°C, whereas at the first stage of hydrolytic polymerization, polymerization is carried out at a temperature of 210-220°C for 9-10 hours, and at the second stage of hydrolytic polymerization, polymerization is carried out at a temperature of 210-220°C for 9-14 hours.

EFFECT: increase in the yield and relative viscosity of high molecular weight polyamide-6.

1 cl, 1 tbl, 1 ex